Using measures of gated-speech understanding performance, the Clinical Investigator Development Award candidate proposes to study listeners' real- time speech understanding and their ability to use contextual cues to "fill-in-the blanks" through the linguistic application of auditory induction known as phonemic restoration. The experimental gated-speech stimuli will contain monosyllabic works in predictability-contrasting contexts and will be presented under three experimental conditions: a) a 60-ms time gating work recognition task; b) a disrupted work recognition task (with and without the addition of a noise masker); and c) a combined recognition task where continuous noise will be added to the gated-out portion of the time-gated stimuli. Specifically, the proposed research will examine how four different types of listeners (young adult, elderly adult, normally hearing and hearing impaired listeners) use acoustic-phonetic and contextual cues to: a) perceive and process dynamically changing ongoing speech and b) perceptually restore missing or masked portions of speech for speech understanding. Two long-term objectives underlie the proposed research, the first is to increase our empirical and theoretical understanding of normal and disordered speech perception and processing. The second is to develop improved speech audiometric procedures for the clinical assessment of a listener's ability to understand everyday "real world" speech.